Operating mechanism for hand-operated devices.



G. M. FLETCHER. OPERATING MBGHANISM POB. HAND OPBRATED DEVICES.

APPLICATION FILED APR.14, 1913.

Patented Apr. 14, 1914.

GAYLE M. FLETCHER, GF BILLINGS, MONTANA.

OPERATING MECHANISM FOR HAND-OPERATED DEVICES.

Specification of Letters Patent.

Application led April 14, 1913.

Patented Apr. 14, 1914. serial No. 760,963.

To all Lo/0m t may concern Be it known that l, GAYLE M. FLETCHER, a citizen of the United States of America, and a resident of Billings, Yellowstone county, Montana, have inve-nted certain new and useful Improvements in Operating Mechanism for Hand-0perated Devices, of which the following is a specification.

My invention relates to improvements in hand-operated engines, and the object of my improvement is to provide mechanism for rapidly rotatino various tools such as circular brushes, bu ers or other devices adapted for dental uses or the like, adapted to be actuated by manual power.

This object I have accomplished by the means which are hereinafter described and claimed, and which are illustrated in the accompanying drawings, in which:

Figure 1 is a transverse vertical section of my improved hand-operated device, taken on the line who of Fig. 2. Fig. 2 is a vertical section of said device, taken on the line c-c of Fig. 1. Fig. 3 is an enlarged elevation of one of the rack-operated gears showing its method of mounting for frietional engagement with its shaft when rotated in one direction. Fig. 4 is an enlarged detail view of the shaft upon which the rackoper ated gears are mounted, the said gears being removed to display the frictional devices inset therein.

Similar numerals of reference denote corresponding parts throughout the several views.

The numeral 12 denotes the longitudinally arranged rotatable operating shaft of my machine, movable within a cylindrical casing 27, the latter having a terminal boxing 28 with a removable cover 31. Upon the upper end of said shaft within said boxing is mounted a bevel-gear 30 in mesh with a bevel-pinion 29, the latter being mounted on one end of a short shaft 32 extending" through the boxing. On the outer end of the shaft 32 is removably secured a tool, such as the circular rotatable brush 33. This tool may be removed and any other suitable tool substituted on said shaft. The lower part 13 of said casing 27 is widened and provided with oppositely-projecting lugs on which the two oppositely-located inwardlytroughed levers 17 and 18 are pivoted on pintles 14. On opposite sides of theshaft 12, spaced therefrom, and seated within the troughs of said levers, are the plates 15 and 16, of like form and pending from the pintles 14 to serve as faceplates for the working mechanism of the device, The troughed levers are formed in a reversely-curved shape so as to be readily and comfortably grasped together within the hand of the operator to not easily slip therefrom when in use. The plates 15 and 16 are rigidly connected by a pair of transverse bars 21 and 22 set upright edgewise, one on each side of the shaft 12, and each having' on its outer face at the bottom a narrow integral shelf having' longitudinal groove along the top.

The numerals 19 and 2O denote a pair of like oppositelylisposed plate springs, whose outer ends are respectively secured to the inner walls of the troughed levers 17 and 18 a little below the middle thereof, and said springs are bent over toward each other in arched forms to extend downwardly to be seated in the longitudinal grooves in the tops of said shelves on the transverse bars 21 and 22. These springs exercise an outward thrust in opposite directions upon the levers 17 and 18, yieldingly.

The lower end of the shaft 12 is mounted in a fixed transverse body 11 secured be- .tween said face-plates 15 and 16 and has on its extremity below said body a bevel-pinion 10 in mesh with a bevel-gear 4, the latter fixed on a rotary transverse shaft 3 whose ends are mounted in bearing-openings in said face-plates.

Referring now to Figs. 3 and 4, the shaft 3 is provided with two like hollowed-out seats 9 and 34 respectively for the small inserted movable rollers 8 and 35. The said seats are reversed in position, and located near each other to lie within the central bearing axial orifices of the pair of gears 2 and 1 respectively, the gears being rotatable on said shaft over said seats and rollers, except as hereinafter stated.

The numerals 23 and 24 denote bearinglugs on the inner faces of the troughs of the levers 17 and 18 near their lower ends, and in which are pintles on which are pivotally mounted the outer ends of the racks 25 and 26 respectively, which are arranged side by side to respectively mesh with the said gears 1 and 2, and rest slidingly upon a fixed transverse bar 7.

To operate the device manually, the levers 17 and 18 are grasped together in the hand of the operator, and swung inwardly dimensions, lixedly deto compress the springs 19 and 20, while simultaneously shifting the said racks over said gears 1 and 2. The grooved seats 9 and 31 are alike, but reversed in position, and each is at one end curved more deeply transfversely to seat the roller therein as shown in Fig. 3, said seat being made more shallow progressively toward its opposite end. llhen one rack rotates the gear Q, for instance, in one direction, the roller S is frictionally rolled from its` seat toward the shallower part of the seat, where it becomes frictionally engaged between the wall of the axial orifice in the gear and the said seat, which thus causes rotation to be communicated to the shaft in one direction, the roller in the other reversely-directed seat 34: remaining in the deeper part of its seat and idly rotating therein, so that the other gear 1 is not able to act upon said shaft when rotated by the other rack. The grasp of the operator now being relaxed upon the levers, the springs 19 and 2O react to push the levers outwardly. The outwardly-moving levers draw back the racks to reversely rock the gears 1 and 2, when the reverse action takes place to that above described upon the rollers S- and 35 in their said seats, and the rack 1 becomes active in rocking the gear 1 to thereby rotate the shaft 3. Since the levers 17 and 18 are kept in motion oppositely as described, the effect of the intermediate mechanism described is to cause a continuous rotation of the shaft 3, since when one rack returns the other rack begins to actuate in its turn to drive the shaft in the same direction.

Since the train of gears described is formed to multiply the speed, the tool 33 is rotated very rapidly, as is necessary in a dental engine, or a tool for manicure service, massaging, or other like uses.

In practice the cased-in part 28-29 may be reduced in dimensions from that shown, so as to be more compact and more conveniently used in restricted cavities.

The device is compact as a whole, easily manually operated by any one, and inexpensive.

Having described my invention, what l claim as new, and desire to secure by Let-f ters Patent, is:

1. In combination, a rotary shaft, man-2 ually-operable bodies located on oppositesides of said shaft and adapted and sup-l ported to be oscillated to and from each`` other, yieldable resilient means bearing against said bodies to yieldingly force them awayfrom each other, racks movably connected to said bodies and slidable past each other oppositely, gear-wheels meshed. with said racks, and operative connections between said gear-wheels and said rotary shaft, said gear-wheels when rotated by said racks being adapted to act upon said operative connections to impart continuous rotation in one direction to said shaft.

2. In combination, a rotary shaft, a fixed support mounted upon said shaft, levers hinged to said support on opposite sides thereof, fixed bodies on opposite sides of the shaft intermediate between Vsaid levers, yieldable resilient means connected between said levers and said fixed bodies and tending to shift the levers apart from each other, racks pivotally connected to said levers and slidable past each other oppositely, gein-wheels meshed with said racks, a rotatable cross-shaft on which said gear-wheels are separately loosely mounted, means for automatically engaging said wheels alternately with said cross-shaft when rocking over it in certain directions to cause the shaft to rotate continuously in one direction, and a gear-train operatively connected between said cross-shaft and the first-mentioned shaft.

3. In combination, a rotary shaft, a fixed casing supported about said shaft, inwardlytroughed levers hinged to opposite sides of said casing, yieldable resilient means bearing against said levers to tend to yieldingly force them apart, covering-plates supported over opposite sides of said device to cover t-he inter-space between said levers, racks pivotally connected to said levers and slidable past each other oppositely, support-ingmeans for said racks, gear-wheels meshed with said racks, a rotatable cross-shaft on which said gear-wheels are loosely mounted, operative connections between said crossshaft and said first-mentioned shaft adapted to rotate the latter at a greater speed than the former, and tight-and-loose engagingmeans located between each gear-wheel and said cross-shaft, adapted to act in driving said shaft continuously in one direction only as the gear-wheels arek alternately reversely rocked by said racks to and fro.

Signed at Waterlomlowa, this 27th day of March, 1913'.

GAYLE u. FLETCHER. Y

Witnesses Gr. C. KENNEDY, W. H. BRUNN.

Copies of this patent may be obtained for five cents each, by addressing the Commissoner'of Patents, Washington, D. C. 

